A mining machine of the type having a rotating cutter drum at a front end thereof can become unstable when the cutter drum is pivoted downwardly relative to the main body portion of the mining machine during the mining operation. This downward pivoting of the cutter drum while the drum is in contact with the earth is often called shearing. When the cutter drum pivots downwardly, the body of the mining machine may tend to lift up from the ground and pivot about the rear end of the crawler tracks.
In the past, a stabilizing arm was connected to the mining machine body and would be pivoted downwardly with sufficient force to embed in the mine floor and thereby anchor the mining machine body so that the mining machine would tend to pivot about the stabilizing arm instead of the crawler tracks. Prior art arrangements suffered from disadvantages including difficulty in arranging piston cylinders and the stabilizing arm in a space beneath a conveyor of the mining machine so that the arm could be brought into contact with the mine floor with sufficient force. U.S. Pat. No. 4,281,879, which is incorporated by reference, discloses a stabilizing assembly that is designed to pivot a stabilizing arm so that a ground engaging arm is brought into contact with the mine floor. By this design, the stabilizing arm will slide along the mine floor as the mining machine sumps forward. This sliding action reducers the available forward thrust. Also, as the machine sumps, the drum rotation offsets the weight of the front of the machine and makes the front of the machine seem lighter, thus transferring the machine""s center of gravity toward the back of the machine. This causes a reduction in the tractive effort because the full length of the crawler chain is no longer in contact with the mine floor during this dynamic situation.
In all prior art designs of mining machines having stabilizing assemblies, whether the stabilizing assembly is of the type that embeds in the ground or otherwise, when the cutter drum shears downwardly as it cuts into particularly hard material, the entire machine tends to try to push backward. It is desirable to provide a stabilizer assembly and a mining machine with a stabilizing assembly that is better suited for preventing backward movement of the mining machine as the cutter drum shears downwardly.
In accordance with one aspect of the present invention, a mining machine having a stabilizing apparatus includes a mining machine and a stabilizing apparatus attached to the mining machine. The stabilizing apparatus includes a turnable stabilizing element and a moving arm attached to the turnable stabilizing element and the mining machine for raising the turnable stabilizing element above and lowering the turnable stabilizing element into contact with a mine floor.
In accordance with another aspect of the present invention, a stabilizing apparatus for a mining machine includes a turnable stabilizing element and a movable arm attached at a first end to the turnable stabilizing element and attachable at a second end to a mining machine for raising the turnable stabilizing element above and lowering the turnable stabilizing element into contact with a mine floor.
In accordance with yet another aspect of the present invention, a mining machine having a stabilizing apparatus includes a mining machine and a stabilizing apparatus attached to the mining machine, the stabilizing apparatus including a stabilizing shoe portion. A piston arrangement is disposed between the stabilizing apparatus and a body of the mining machine. The piston arrangement is adapted to move the stabilizing shoe toward a rear of the body.